GHC head 8.1.20170209 does not compile package 'mono-traversable'

Not sure if this is a bug in 'mono-traversable' or GHC but I thought it was worth reporting in any case. GHC head 8.1.20170209 is the version used:

    Configuring mono-traversable-1.0.1.1...
    Preprocessing library mono-traversable-1.0.1.1...
    [1 of 5] Compiling Data.MonoTraversable ( src/Data/MonoTraversable.hs, .stack-work/dist/x86_64-linux/Cabal-1.25.0.0/build/Data/MonoTraversable.o )
    
    /tmp/stack12856/mono-traversable-1.0.1.1/src/Data/MonoTraversable.hs:144:13: error:
        • The default type signature for omap:
            forall (f :: * -> *) a.
            (Functor f, Element (f a) ~ a, f a ~ mono) =>
            (a -> a) -> f a -> f a
          does not match its corresponding non-default type signature
        • When checking the class method:
            omap :: forall mono.
                    MonoFunctor mono =>
                    (Element mono -> Element mono) -> mono -> mono
          In the class declaration for ‘MonoFunctor’
        |
    144 |     default omap :: (Functor f, Element (f a) ~ a, f a ~ mono) => (a -> a) -> f a -> f a
        |             ^^^^

Trac metadata

Trac field	Value
Version	8.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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